New Zealanders have flocked to bars, restaurants, music festivals and waterfront vantage points to catch stunning fireworks displays as they celebrate the New Year 2019.

But as the booze begins to flow freely around the country and behaviour rapidly descends into revelry, Kiwi emergency services are “gearing up” for their most demanding night of the year.

Australians too have welcomed the new year with dazzling fireworks in Sydney.

Australia’s largest city Sydney put on its biggest-ever fireworks display in a spectacular welcome to the New Year, kicking off a wave of celebrations for billions around the world.

A record amount of pyrotechnics as well as new fireworks effects and colours lit up the city’s skyline for 12 minutes and dazzled the more than 1.5 million spectators who packed the harbour front and parks.

An earlier thunderstorm did not dampen the spirits of revellers who camped out at vantage points, some since the early hours of the morning.

To mark the international year of indigenous languages in 2019, the harbour also hosted a ceremony celebrating Aboriginal heritage that included animations projected onto the bridge’s pylons.

The party atmosphere will sweep across major cities in Asia, Europe, Africa and the Americas as the clock ticks past midnight.

A strong police presence has become a key element of the festivities, to protect crowds that could be targeted in terror and vehicle attacks. (NAN)